Evaluation of Disinfectants on Military NATO and DECON Litters

Abstract

OBJECTIVE: This study evaluated the effectiveness of five disinfectants: A33, 10% bleach, 1% bleach, SPOROX, and 3% H₂O₂, on military NATO and DECON litters.

DESIGN: Suspensions of Acinetobacter baumannii, Staphylococcus aureus, and spore-enhanced Bacillus subtilis, with five percent albumin, were inoculated onto litters and dried overnight. The litters were saturated with disinfectant solutions and sampled after 10 minutes. The Log₁₀ reduction in the number of bacteria recovered was calculated.

SETTING: 59^th Medical Wing, 59^th Clinical Research Division, Lackland AFB TX.

MAIN OUTCOME MEASURES: A reduction of ≥3 Log₁₀ in the number of bacteria recovered from the test squares compared to the control squares was considered effective disinfection.

RESULTS: On the NATO litter 10% bleach and SPOROX were effective against vegetative cells. On the DECON litter A33, 10% bleach, and SPOROX were effective against vegetative cells. After the 10 minute exposure none of the disinfectants evaluated were effective against spore-enhanced B. subtilis.

CONCLUSION: When contaminated with vegetative cells military NATO and DECON litters can be effectively dis-infected with a 10 minute exposure to some disinfectants. Further research is needed to find an effective disinfectant for spore contamination.

ABBREVIATIONS: AFB = Air Force Base; ATCC = American Type Culture Collection; BAMC = Brooke Army Medical Center; BSA = bovine serum albumin; CFU = colony forming units; D/E = Dey/Engley; DECON = decontamination; H₂O₂ = hydrogen peroxide; NAM = nutrient agar with manganese sulfate (50 μg/mL); NATO = North Atlantic Treaty Organization; QAC = quaternary ammonium compound; SBA = Trypticase soy agar with five percent sheep's blood.